1. Field of the Invention
The present invention relates generally to a novel vacuum system, and more specifically, to an apparatus for cleaning dust, dirt, and debris from the footwear of a pedestrian entering a building.
2. Description of Related Art
A variety of proposals have previously been made to control the tracking of dust, dirt, and debris caused by the footwear of a pedestrian entering a building. The most basic means is a doormat upon which the pedestrian wipes his or her shoes prior to entering. However, even when the shoes are relatively clean the doormat does little to remove and retain any debris and often contaminates the shoes of other pedestrians who may follow.
U.S. Pat. No. 4,024,599 (Gamboa) discloses an apparatus for cleaning the bottom of a wearer's shoes. The apparatus in Gamboa, a “Shoe Cleaning Machine” as illustrated in FIG. 1A, is a free-standing machine that has a platform upon which the wearer stands. Once activated, the machine physically scrubs debris from the wearer's shoes with bristles attached to a motorized belt while an integral fan carries the debris to a removable bag located in the housing. One of the drawbacks to Gamboa is that the machine is physically impractical for use in other than industrial settings. In addition, Gamboa utilizes a motorized belt with bristles that physically scrub a wearer's shoes, resulting in increased wear, maintenance and operating expense.
U.S. Pat. No. 4,027,355 (Mead et al.) discloses a pneumatic cleaning mat that provides positive cleaning action of a pedestrian's footwear. The mat in Mead et al. utilizes a pressurized tank of air that discharges through poppet valves located on the top surface of the mat when a pedestrian steps upon the mat. Thus, attached debris is blown away from the footwear. Because Mead et al. requires compressed air, its operation would likely result in debris being blown unpredictably about which could result in physical injury to a user. Also, the discharge of air would likely be noisy, making the device impractical for other than industrial settings. Maintenance of the poppet valves would likely be financially and physically burdensome, resulting in significant operating expense.
U.S. Pat. No. 4,551,879 (Ray) discloses an entrance dust arrester that vacuums the area directly under a door as it swings on its hinges. The vacuum in Ray, as illustrated in FIG. 4, is integral with the door, with the suction on the bottom of the door positioned such that it can vacuum the mat lying beneath. Thus, an individual who walks through the door and steps on the mat will leave debris on the mat which will be vacuumed upon closing the door. Ray requires a user to physically scrub their footwear on the mat beneath the door and then rely on the door to vacuum any debris away. Thus, if the user swings the door too quickly, the vacuum may be ineffective in cleaning the mat and the next individual to enter may end up tracking the debris that should have been previously captured. Also, this device requires extensive modification to an existing door which would increase installation, maintenance, and operating costs.
U.S. Pat. No. 6,067,688 (West) discloses a shoe cleaning device for scrubbing and vacuuming shoes. The device of West, as illustrated by FIG. 3, is either portable or else mounted in the floor of an entrance. Individuals entering would step on the device and wire bristles would physically scrub the individual's shoes. Debris would be carried away from the bristles by a powerful squirrel cage fan mounted directly beneath the top surface of the device. West requires significant space to house the internal components as disclosed. Thus, the physical size of the West device would make it impractical for use in other than industrial settings. Also, West requires both a squirrel cage fan and a vacuum source which increases expense and maintenance costs, further making it impractical for use in other than industrial settings.
Other prior proposals include footwear cleaning means utilized in semiconductor fabrication clean rooms such as the Sole Cleaner™ Automatic Contamination-Control Mat (illustrated by FIG. 2) and the Motorized Shoe Cleaner (illustrated by FIG. 1B), both offered by Terra Universal, Inc. The Sole Cleaner™ is similar to other clean room contamination-control offerings that utilize a mat with a sticky surface that physically adheres to debris on footwear. Prior to entering a clean room, the individual would walk across the sticky surface of the mat to remove debris from the bottom of his or her shoes. After a fixed number of uses, the sticky-mat surface must be changed. The Motorized Shoe Cleaner operates much the same as Gamboa in that it is a free-standing machine upon which an individual would step prior to entering a clean room. The Motorized Shoe Cleaner would then be activated to physically scrub debris from the individual's shoes and vacuum the debris away. Because of the increased number of components that wear and need to be replaced frequently, both of these devices require significant maintenance and operating expenditures that make them impractical for use in other than industrial settings.
Nothing in the prior art addresses the problems associated with providing a footwear cleaning means that is practical for use in an other than industrial setting. Therefore, a need exists for an improved footwear cleaning device that is suitable for use in residential, commercial, and industrial situations. Further, a need exists for an improved footwear cleaning device that is compact, quiet, and aesthetically attractive. And further, a need exists for an improved footwear cleaning device that requires relatively little maintenance and is inexpensive to operate. The present invention fills these needs and other needs as detailed more fully below.